"I don't come as a know-all who is going to pontificate and tell you Canadians what you must do," he told reporters Friday before opening a two-day conference on oilsands development and First Nations treaties in Fort McMurray.
"I think I can almost say, without fear of contradiction, that you do know what you should do."
But he didn't minimize his assessment of how serious a threat climate change poses. Effects are already being felt all over the world, he said, citing stories people have told him from Norway to Nigeria.
"We are sitting on a powder keg if we don't do something urgently, quickly."
Tutu suggested we are all members of one global family who should look out for each other.
"It is better working together than being at loggerheads, at daggers drawn," he said. "It is far better — it is cheaper — for people to be friends than enemies."
He pointed to his own experience fighting the apartheid regime in South Africa as an example of people can work out even the toughest problems.
"We could have had one awful conflagration," he said. "It didn't happen."
The archbishop, who won the Nobel Peace Prize for his role in the fight against apartheid, has taken strong stands on climate change and against projects such as the Keystone XL pipeline. Tutu has signed a petition against the project. In an opinion column earlier this year in the British newspaper the Guardian, the 82-year-old called the Keystone proposal to move oilsands bitumen from Alberta to the U.S. appalling.
He has also called for boycotts of events sponsored by the fossil fuel industry, for health warnings on oil company ads and for divestment of oil industry investments held by universities and municipalities, similar to measures that were brought against South Africa's old apartheid regime.
"It is effective," he said, emphasizing the statement with a loud cry and throwing his hands in the air.
Tutu brought a religious bent to a debate often restricted to science and economics. "The Bible says God said to Adam, 'Till it and keep it.' Not 'Till it and destroy it.'"
Tutu was to take an aerial tour of the massive oilsands development Friday afternoon, but heavy winds put that in doubt. There were no plans for him to meet with industry officials during his time in Fort McMurray.
Some in the oilsands capital seemed open to hearing what he had to say.
Syncrude employee Melvin Campbell said he feels Tutu's opinion carries more weight than that of others who have been critical of the industry.
"He has a little bit more credibility than the actors and the players," said Campbell. "Desmond Tutu has a lot of political experience and the public's ear. I hope he uses it well."
Earlier this year, musician Neil Young played concerts in several cities to support the Athabasca Chipewyan First Nation after he visited the region. In 2010, Hollywood director James Cameron toured the oilsands and the community of Fort Chipewyan.
Oil worker Jay Hardy said Tutu's words should be heard.
"He has a good idea of the way that the world should be with the environment and with people living in it," Hardy said. "I respect the man. I think we all should. He has good philosophy."
Brigitte Mbanga said whatever Tutu has to say is still only one man's opinion.
"He is a more prominent person than the Hollywood celebrities that have come here," she said. "His comments may be helpful to the government or the oilsands, but it's like every other person's comment."
The conference is intended to discuss the need for renewal of treaty relationships in light of extensive resource development such as the oilsands.
It's co-sponsored by the Athabasca Chipewyan First Nation and the Toronto law firm Olthuis Kleer Townsend, in which former Ontario premier and one-time federal Liberal leader Bob Rae is a partner. Rae is scheduled to be one of the speakers. So are former Northwest Territories premier Stephen Kakfwi and former Syncrude Canada president James Carter.
Representatives from the Alberta and federal government are not expected to attend although they were invited, said conference spokeswoman Eriel Deranger.
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